Nimotop (Nimodipine) is used to decrease problems due to a certain type of bleeding in the brain (subarachnoid hemorrhage-SAH). Nimodipine is called a calcium channel blocker. The body naturally responds to bleeding by narrowing the blood vessel to slow blood flow. However, when the bleeding is in the brain, stopping blood flow causes more brain damage. Nimodipine is thought to work by relaxing narrowed blood vessels in the brain near the area of bleeding so blood can flow more easily. This effect reduces brain damage.This medication should not be given by injection. Accidental injection of nimodipine can cause serious (rarely fatal) side effects (such as low blood pressure, slow heartbeat). Consult your doctor or pharmacist for details.